It was a very good night for Oliver Knussen Sunday at New England Conservatory’s Jordan Hall. Not only did he receive an honorary degree, but in the concert by the Boston Modern Orchestra Project two of his works, written when he was barely old enough to go to college, were easily the class of the field.

The Glasgow-born composer-conductor, who turned 60 last year, sat in the audience near the stage as Gil Rose led the BMOP in Music for a Puppet Court, an intriguing puzzle piece whose origins date from when he was 20, and the darkly evocative Symphony No. 2, composed at 19 and the earliest piece Knussen has allowed to remain in his catalogue.

Rose also led brisk performances of Alberto Ginastera’s Harp Concerto and Michael Gandolfi’s 2012 piece, The Nature of Light.

In a rather elaborate play on Knussen’s nickname, his fondness for childlike subjects like riddles and games, and the lack of an admission charge for this concert, the BMOP’s wordsmiths titled this program “Olly, All Ye, In Come Free.”

In 1972, Knussen became intrigued with musical puzzles attributed to Henry VIII’s court composer, John Lloyd. He composed solutions to two of them in more or less Tudor style, then wrote a variation on each in his own bright, fanciful modern idiom. A decade or so later, he fulfilled a commission by reworking this material as Music for a Puppet Court.

As the title implied, there was an air of make-believe, of dress-up, to the proceedings Sunday night. Modern instruments such as guitar, harp, flutes and clarinets managed to evoke the sounds of four-and-a-half centuries ago, as the old puzzles’ intricacies of pitch, meter, and duration clicked into place.

The first variation movement got the canon dancing in dry pizzicato amid brilliant high sonorities of winds and percussion. In the second, the double orchestra set smooth strings against intrusions by an Ivesian marching band in a different tempo. Rose and his players were alert to every nuance of the piece’s old-new dialogue.

Following that piece’s four brief movements, a long break was needed to set the stage for the Ginastera concerto. The choreography of set-up at a contemporary music concert is always part of the show, but this event in particular seemed almost to devote more time to moving furniture than to the four concise pieces on the program.

Although composed less than a decade before the still-fresh-sounding Knussen works on this program, Ginastera’s 1965 Harp Concerto sounded very much of its time, observing the old conventions of three-movement concerto form, dissonant enough to sound modern, and syncopated enough to sound Latin American.

Harpist Krysten Keches, winner of the 2012-13 BMOP/NEC Concerto Competition, made the most of this somewhat conventional score with an impressive display of hands-on music-making. Listeners who know the harp mainly as a nice touch of color in orchestral scores might have been amazed at the variety of sonorities, articulations, and effects Keches drew from her instrument, from the most evanescent filigree to hard-edged forte chords virtually ripped from the strings.

Ginastera wrote loud and brassy for the orchestra, and conductor Rose didn’t hold it back, but the harp is a big, resonant instrument, and Keches held her own amid the pounding Latin beat. Her elegant, malleable phrasing in slow tempos and fast would be the envy of many pianists, and it’s unlikely any player of a box with hammers could match the range of sounds, hard and soft, wet and dry, fragile and massive, that fingers on strings produced in this performance.

The solo cadenza before the concerto’s finale was of course a catalogue of these harp sonorities, but what was more impressive was the way Keches slipped smoothly in and out of them throughout the piece, as the expression of the music demanded. It’s reported that composing a concerto for harp gave Ginastera no end of trouble, but this harpist and this orchestra made it sound like the most natural thing in the world.

Following the intermission, Oliver Knussen came onstage with NEC president Tony Woodcock and composition faculty member Kati Agócs for the awarding of NEC’s honorary Doctor of Music degree. Agócs began by praising the composer for music that “jumps off the page, grabs and entrances the listener.” President Woodcock read from the degree citation, calling Knussen “a major force in illuminating contemporary music’s complexity and intensity.”

Then it was time for dress-up, as Agócs stood on tip-toe to arrange the black-and-yellow satin doctoral hood over the composer’s hulking, turtlenecked frame. After pronouncing himself “very, very touched” by the honor, Knussen exited the stage, looking a bit like a very large trick-or-treater in a Superman cape.

Gandolfi’s The Nature of Light followed, a piece in two fairly brief movements for clarinet and orchestra. Although it came wrapped in an aspirational title and much program-notery about waves, particles, relativity, mensural canons and the like, in performance the piece seemed like thin stuff indeed.

In the first movement, a Coplandesque string chorale, repeated over and over with embellishments, was billed as a “passacaglia.” The second at least had some variety of tempo and fast tootling for soloist Laura Ardan, but the themes lacked interest; the movement’s sonata form dictated that they all be recapitulated at full length, not something greatly wished for at that moment.

Ardan, the longtime principal clarinetist of the Atlanta Symphony Orchestra, played with full, clear tone and admirable energy, but wasn’t able to raise this score above its limitations.

In his Symphony No. 2, a compact work in four movements for small orchestra and soprano solo, the 19-year-old Knussen set enigmatic texts by two depressive poets, the Austrian Georg Trakl and the American Sylvia Plath, producing music that was subtle and suggestive beyond his tender years.

Unfortunately, lights in the hall were too low to follow the text during the performance, but soprano Sonja Tengblad’s clear diction helped remedy that. Tengblad’s extraordinarily pure tone, with moderate vibrato, was consistent across her wide range, from stratospheric soft high notes to strong low ones, and made a fine timbral match with the orchestra’s prominent woodwinds, especially flutes and horns.

Tengblad’s performance strove for no big effects, but instead subtly declaimed the texts and helped weave the work’s dark atmosphere. (The piece contained few explicit musical images, except when scurrying strings announced the arrival of Trakl’s “Rats.”)

The soprano negotiated Knussen’s disjunct vocal line with the kind of pinpoint intonation and consistency of tone that made it, too, seem perfectly natural. At the piece’s end, her flute-like voice gave way to the sound of an actual flute, playing all by itself.

How many 19-year-old composers would end a symphony that way? It seemed a fitting way also to end an evening’s tribute to the large and modest man who wrote those notes 42 years ago.

The next program of the Boston Modern Orchestra Project, titled “Gen OrchXstrated,” will be 8 p.m. May 17. bmop.org; (781) 324-0396.